Manufacture of steel-sheathed tubing.



E. I. HICKSON.

MANUFACTURE OF STEEL SHEATHED TUBING.

APPLICATIOII FILED JUNE I2, IBIS. 1 205 742, Patented Nov. 21, 1916.

FIGJ- WITNESSI INVENTOR.

ATTORNEY EDWIN J. HICKSON, OF BUTLER, PENNSYLVANIA.

MANUFACTURE OF STEEL-SHEA'IHED TUBING.

Specification of Letters Patent.

Patented Nov. 21, 1916.

Application filed June 12, 1915. Serial No. 33,693.

'1 b all whom it may concern Be it known that I, EDWIN J. I-IIoKsoN, acitizen of the United States, and resident of Butler, in the county ofButler and State of Pennsylvania, have invented certain new and usefulImprovements in the Manufacture of Steel-Sheathed Tubing, of which thefollowing is a specification.

The method of the present invention is directed to the manufacture ofsheathed tubing, and has particularreference to applying a sheathing ofpolished steel or equivalent material to a tubular or other core ofrelatively inexpensive steel or iron without distorting the sheathing orinjuring or marring its surface.

While the product of the present invention is designed primarily for usein metal bed frames, it may be used wherever material of this nature maybe utilized to advantage, and obviously the invention is not restrictedto applying the sheathing to a tubular core, nor to a core of anyparticular cross-sectional shape.

Brass sheathed tubing is extensively used, particularly in themanufacture of metal beds, the sheathing and tubular core beingordinarily drawn through steel dies which shape the sheathing closely tothe core, and by the same operation the longitudinal edges of thesheathing are seamed and interlocked, this without injuring the finishedsuface of the sheathing. In attempting to similarly apply thin andpolished steel sheathing, the considerable friction between thesheathing and the steel dies caused by the high pressure incident to thedie operation has resulted in so dragging, distorting and marring thesheathing as to render the product unfit for use. Also, the heatresulting from such friction sets up an amalgamating tendency betweenthe like metals of the sheathing and dies that is an important damagingfactor. So far as I am informed, polished steel sheathed tubing has notheretofore been successfully manufactured, at least by a process whereinthe sheathing and core are united when in a cold state and with thesurface of the sheathing given itsultimate finish prior to applying itto the core.

The method of the present invention'entirely overcomes the difiicultiesnoted as by means thereof I am enabled to produce polished sheathedtubing without flaw or blemish and at the same manipulation cost as thatincident to the manufacture of brass sheathed tubing.

The essential feature of the invention is the provision of dies formedof a metal that will neither distort nor amalgamate with the thin steelsheathing nor mar its polished surface under the pressure necessary toconform and secure the sheathing to the core. I successfully accomplishthis result by the use of dies formed of brass, the steel sheathedtubing thus produced being as perfect in every particular as the bestquality of brass sheathed tubing. In shape or contour the dies are nodifferent from steel dies used in the brass sheathing process, and themethod of manipulating the core and sheathing does not differ from thefamiliar practices incident to the manufacture of brass sheathed tubing,the core and the thin and highly polished ribbon-like sheathing beingpassed through the dies in the usual manner and the edges of thesheathing are seamed and jointed together by any of the seaming orjointing devices well known in the trade.

IVhile I have successfully practised the new method by the use ofbrassdies, I do not confine myself thereto as the invention contemplatesdies formed of any other metal or alloy which will accomplish the sameresult in the application of thin and polished steel sheathing to ametal core.

Apparatus for practising the invention may be variously embodied. Anadaptation of mechanism, largely diagrammatic, is illustrated in theaccompanying drawings, wherein Figure 1 is a view in longitudinalsection of dies suitable for the purpose, and Fig. 2 is a Viewillustrating portions of the core and sheathing before and after theyhave been united.

In the drawings, A designates an initial or forming die, and B and C,respectively, are finishing dies through which the material passes afteremerging from die A. The dies may be mounted in any suitable frame orhead conventionally illustrated at D, and a portion E at the front ofthe latter may be utilized as a support for any suitable seaming ofjointing device, not shown.

F designates a metal core, here shown of tubular form, and G is asheathing of thin and highly polished steel which is passed to the diesin ribbon form, as is customary in the manufacture of brass sheathedtubing.

Various devices are well known in the art for seaming and jointing thelongitudinal edges of been conformed to the metal'core, and I thereforedeem it unnecessary to illustrate any particular form of jointing orseaming mechanism.

It will be understood that the disclosures in the accompanying sheetsteel and while cold drawing the core I and ribbon of steel throughfinishing means composed of brass or equivalent material that will forcethe steel ribbon to inclose and tightly conform to the core withoutdistorting or marring the surface of the steel, substantially asdescribed. I

2. The method of producing sheathed cores which consists in bringingtogether the core and a ribbon of thin sheet steel having its exteriorsurface previously polished and drawing the core and steel ribbonthrough tube conforming metallic means of higher specific gravity thansteel that will not amalgamate with the polished surface of the steelribbon in the presence of heat and pressure incident to such drawing,substantially as described.

Copies of this patent may be obtained for the sheathing after the"latter has o 3. The. methodof tightly inclosing cores in steelsheathing to produce steel sheathed tubing having a smooth and polishedouter surface, which consists inapolying a ribbon of thin sheet steelhaving a smooth and polished exterior surface to the core, and

longitudinally drawing the core and steel ribbon throughforming andfinishing dies,

the finishing dies'being composed of metal.

of different density and softness thansteel and that will notamalgamatewith steel under heat andpressure incident to such drawing,substantially as described. 7

at. The method of producing sheathed cores which consists inlongitudinally bringing together a cold core and a ribbon of cold thinsheet steel havinga .smooth'outer surface, and drawing the coreand steelribbon while held under compression by copper alloy conforming meansthat will forcethe steel ribbon to tightly inclose the core withoutdistorting or marring the smooth surface of the steel. 7 I

5..The' method of permanently and tightly inclosing cores in steelsheathingto produce steel sheathed tubing having a smooth outer surface,

gitudially applylngto the core when cold a which consists in 1011-ribbon of th1n cold sheet steel having a smooth exterior surface, andfolding the ribbon around the core and drawing the core and steel ribbonthrough a finishing die composed of copper alloy, substantially as andfor the purposes described.

in testimony whereof I. affix my signa ture in presence of twowitnesses.

Witnessesi FRANK Fnos'r,

L. RowLEN.

five cents each, by addressing the Commissioner of Bate'nts,

' Washington, D, G.

EDWIN J. HICKSON. 1

